Mechanism for producing axial reciprocation



July 6, 1937. c. H. cooLlDGE ET Al. 2,086,401

MECHANISM FOR PRTODUGING AXIAL RECIPROCATION Filed Jan. 15, 1957 M Y L ciu/m,

1 @FFW Patented July s, 1937 MECHANISM FOR PRODUCING AXIAL 1 RECIPROCATION Charles H. Coolidge and Leland F. Remington,

Worcester, Mass., assignors to Curtis & Marble Machine Company, Worcester, Mass., a, corporation oi Massachusetts Application January 1s, i931, serial No. izasaz e claim. (cl. 'i4-57) This invention relates toY mechanism for produclng axial reciprocation of a rotated shaft or cylinder or other rotated member. It is desirable isn many instances to produce such axial reciprocation in order to distribute wear on the rotated part and also to permit more perfect and uniform work to be produced.

Our invention is particularly applicable to textile shears and to other machines having elon- 'gated revolving cutters or elongated grinding cylinders or rolls.

It is the general object of our invention to proafter described and more particularly pointed out in the appended claims.

Preferred forms of the invention are shown in the drawing, in which Fig. 1 is a sectional side elevation of one form of our improved reciprocating mechanism;

Fig. 2 is a partial sectional end elevation, taken along the line 2-2 in Fig. 1; i.

Fig. 3 is a partial side elevation of a modified construction; Fig. 4 is an end view looking in the direction ofthe arrow B in Fig. 3; and

Fig. 5 is a partial side elevation pf a further modification.

Referring to Figs. 1 and. 2, we have shown our invention incorporated in a bearing support Il of a rotated shaft II. The shaft il may for illustration be an amature shaft for a motor M and may have an armature I2 mounted thereon.

A collar I5 is secured to the shaft II by a setscrew I6 and preferably has a stud I4 extending into a slot 'I9 in .the end of a sleeve 20 lwhich snugly fits the shaft I I. A second sleeve 2I abuts the sleeve 20 and lmay have a slot 22 to receive .a stud 23 in a sleeve or collar 24 which is secured to the shaft II .by a set-screw 23. All of these parts are thus secured to rotate with the shaft I.

A series of rolls 30 forma roller bearing for"A the sleeve 20 on the shaft II and are enclosed '55 by an outer sleeve or racejl, mounted in the casing III and held from rotation in any convenient manner, as by .a pin 32.

A disc 33 is mounted in the casing II) adjacent one end of the outer sleeve or race 3| and said disc' is loose on the sleeve 20. A pack- 5 ing :i3a is preferably provided in an annular groove in the disc 33, and a similar packing 34 is provided in a similar groove in the end wall of the casing I0. The packings 33 and 34 prevent axial escape of the grease in which the rolls 3U l0 commonly rotate.

An inner race 40 of Va ball bearing is loosely mounted on the sleeve 2l and has a denlte clearance relative thereto. This clearance may be. varied in amount for a reason to be'explained, but 15 a difference of 0.02" in diameter between the inside ofy the race 4I) and the outside of the sleeve 2l may be considered an average clearance.

The usual balls- 42 are mounted between the inner race 40 and an outer race 45. The outer 20 race is providedat one pointl with a stud or projection 46, extending outward intoa passage or opening 41 which is threaded to receiveF a pressure adjusting screw 48. A spring 5I! is mounted between the screw 48 and the ring 45 and is held 2 5 in position by the projection 46 on the race 45 and a similar projection 49 on the inner end of the screw 48.

The race 4151s thus held from rotation and the whole ball bearing is firmly pressed against a por- 30 tion of the sleeve 2l by the spring 5.0, with the amount ofr pressure determined by the setting of the screw 43.

ill ring is mounted on an extensionof. the inner race 40 andmay besecured thereto by a 35 screw 53. A stud GII is mounted in the ring and projects axially therefrom to engage the side surface 6I of a cam 62, mounted on. the sleeve 2| and secured thereto by a screw 63.

The casing I0 may have a removable end plate 40 65 secured thereto by screws 6.6 and preferably provided with a packing 61 in its inner edge portion, so that the ball bearing and associated parts mayruninoilifsodesired. 'f

Having described the 'details of construction of 45 this form of our invention, we will now describe `the manner in which axial reciprocation of the shaft II is produced.

-As the shaft II and sleeves 20 and 2| rotate, the inner ball bearing race 40 will roll on the 50 sleeve 2i and incluse contact with the portion of the sleeve surface adjacent the spring 50. The inner diameter of the race 40 is, as stated, slightly but definitely greater than the outer diameter 0f the sleeve 2l. vConsequently the rolling con- 55 tact of the race and sleeve at one point only will cause the race to rotate at a diierential speed which is very slightly less than the speed of th lshaft Il and sleeve 2|. For instance, if the shaft II and sleeve 2| are rotated at 1200 revolutions per minute, the race 40 may rota-te at a speed which is one percent less, or at 1188 revolutions. 'I'he ring 55 and stud 60 rotate with the race 40, while the cam 62 rotates with the sleeve 2l. Consequently for every 1200 revolutions of the cam 62, the ring 55 andstud 60 will make only 1188 revolutions. In other words, the cam 62 will make one revolution relative to the ring 55 and stud 60 for every 100 revolutions l5 of the shaft Il.

Every revolution of the cam 62 relative to the stud 60 will obviously force the shaft Ii a limited distance tothe right in Fig. 1 and will also allow time for the shaft to be returned to the left by 2o any suitable means to complete the reciprocation.

In the motor drive shown in Fig. 1, the armature I2 will be axially displaced in its magnetic eld when the shaft I I is shifted to the right, and the pull of the magnetic forces on the displaced 25 armature will tend to move the armature and shaft toward the left and to center the armature axially, thus providing the necessary means to complete the reciprocation.

The extent of the reciprocating movement is 30 determined by the contour of the cam 62, and the relative speed of reciprocation is determined by the amount of clearance between the sleeve 2i and the inner race 40. The greater the difference in diameter and the greater the resulting clear- 35 ance, the greater will be the dierence in speed.

of rotation between the ring 55 and stud 60, and the cam 62, and the more rapid will be the reciprocation. In Figs. 3 and 4 we have shown a construction 40 in which a yoke lever 15 and spring T6 are provided to return the shaft I I to the left to complete the reciprocation.

In Fig.l 5 we have shown a construction in which an arm 80 on a ring 8| has a roll 82 which pro- 45 jects into a groove 83 in the periphery of a cam 8l, so that the cam itself will control the re- `ciprocating movement in both directions. The

ring 8| corresponds to the ring 55 in Fig. 1.

Having thus described three different forms of 50 our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what we claim is:-

1. Mechanism for producing axial reciproca- 55 tion of a rotated member comprising two sbstantially concentric coacting members, one o f which is driven, said coacting members having surfacesof slightly different diameters which are in rolling contact lwith each other and which 60 thereby cause said members to rotate at differential speeds, and means rendered operative by said differential speeds to move said rotated member axially. 2. Mechanism for producing axialv reciproca- 65 tion of a rotated member comprising two coacting members both rotating substantially about the axis of said rotated member and one of which is driven, said coacting members having surfaces of slightly diiferent diameters which are in roll- 70 ing contact with each other and which thereby cause Vsaid members to rotate at differential speeds, and cam means rendered operative by said grlgntial speeds to move said rotated member 75'` 3. for producing iiprocation of a rotated member comprising two coacting members substantially concentric with said rotated member, said coacting members having surfaces of slightly different diameters which are in rolling contact with each other and which 5 thereby cause said members to rotate at dinerential speeds, means controlled in its operation by said differential speeds effective to move said rotated member axially in one direction, and means to restore said rotated member to initial axial l0 position.

4. Mechanism for producing axial reciprocation of a rotated member comprising telescoping members both rotating substantially about the axis of said rotated member, said coacting members means to restore said rotated member to initial axial position.

5. Mechanism for producing axial reciprocation of a rotated member comprising two coacting members both rotating substantially about the axis of said rotated member, said coacting members having surfaces of 4slightly different diameters which are in rolling contact with each other and which thereby cause said members to rotate at differential speeds, means controlled by saidv differential speeds effective to move said rotated member axially in one direction, and electromagnetic meansto move said rotated member in the opposite direction.

6.. Mechanism for producing axial reciprocation of a rotated member comprising two coacting members both rotating substantially about the axis of said rotated member, said coacting members having surfaces of slightly different diameters which are in rolling contact with each other and which thereby cause said members to rotate at differential speeds, means controlled by said differential speeds effective to move said rotated member axially in one direction, and spring means to yieldingly restore said rotated member to initial position.

7. Mechanism for producing axial reciprocation of a rotated member comprising two coacting members substantially concentric with said rotated member, said coacting members having surfaces of slightly differenti diameters which are in rolling contact with each other and which Ythereby cause said members to rotate at differential speeds, means controlled in its operation by said differential speeds eective to move said rotated member axially in one direction, and a double acting cam controlled in its operation by said differential speed and effective to reciprocate said rotated member. 8. Mechanism for producing axial reciprocation of a rotated member comprising telescoping members having a definite but relatively slight difference in diameter between the outer diamef ter of the inner telescoping member and the inner diameter of the outer telescoping member, y said inner member being mounted on and rotating with said rotated member and said outer member rolling on said inner member, a cam mounted to rotate with one of said telescoping members and a device mounted to rotate with the other telescoping member and engaging said cam, said telescoping members rotating at'diiferential speeds, and said cam and device effecting axial movement of said rotated member. 76

9. Mechanism for producing axial reciprocation of a rotated member comprising telescoping members having a. denite but relatively slight difference in diameter between the outer diameter of the inner telescoping member and the inner .diameter of the outer telescoping member, said inner member being mounted on and rotating with vsaid rotated member and said outer member rolling on said inner member, a side cam mounted 

